An Independent evaluator that has been testing the prototypes has reported a battery only powered ArduRf1s running for 80 hours sending a 40 byte message once every 5 seconds. This was done WITHOUT putting the ArduRf1s and the radio in Low Power Sleep mode.

My target is to have a thirty day battery life with minimal power saving while transmitting once a minute. If we assume (naively) that sleeping the radio for 55 seconds per minute will get a six fold battery life increase then we are already at 480 hours or twenty days.